Mere Christianity is a work derived almost completely from radio broadcasts originally done on BBC radio in England during World War II. Lewis largely wanted the book to read as a talk (5), and that is indeed how it reads. It is familiar, warm, and yet cuttingly insightful when it comes to the condition of man and the truth-claims of what he calls “mere Christianity.” His main goal was to state the basic, core beliefs that virtually all Christians across history have held to be true and do so in a way that accounted for their plausibility.
The work is actually divided into four books (which should rather be called “parts”). The first book features Lewis unraveling his masterful use of the moral argument for God’s existence. He wrote quite methodically; not attempting to go too fast, he wanted to claim only what his argumentation had warranted, and nothing further.
First, Lewis argued that everyone has a particular concept that there is an objective moral standard, and that this standard dictates what is right and wrong. He argues for universal perception of this moral law, in part, by stating that no one ever tries to simply shrug off the standard. Instead, they argue that they meet the standard, or there is some particular circumstance that excuses them in this case, and so on. He puts it like this: “Quarrelling means trying to show that the other man is in the wrong. And there would be no sense in saying that a footballer had committed a foul unless there was some agreement about the rules of football” (16). As an aside, Lewis excels at showing his point by way of analogy.
Lewis then deals with objections to the moral law, showing that it is not merely social convention or useful behavior by using counterexamples from everyday life (26). He closes this chapter by pointing out this means there is “a real law, which none of us made, but which we find pressing on us” (27). He has not yet argued about who or what made this law, but has established that we all think it to be there. After this, he closes the first book with two main contentions. First, that there is a higher power that created these moral obligations. Second, Christianity is the remedy for those who have broken the moral law—which is all of us (35). This serves as a good segue into the next book.
The second book concerns Christian doctrine in particular, and how it differs from other religions. Lewis argues that Christianity must be more than a pagan kind of dualism, because one of the sides is good, and thus is a better representative of an objective moral standard than the other. Thus, the two sides are not really equal, and only one of them is God (44). Christianity also has a remedy for sin, and that is found in the person of Jesus Christ. This is where Lewis’ famous trilemma appears: Jesus is either a liar, lunatic, or Lord (50-51). This weight presses upon the skeptic as Lewis moves to the third book.
This book concerns Christian behavior. Lewis nicely defines morality according to three parts: “fair play and harmony between individuals . . . harmonising the things inside each individual. Thirdly, with the general purpose of human life as a whole;” he also argued that most people are only ever concerned with the first part, to their detriment (67). He then speaks of the cardinal virtues, and argues that each act makes a man more like heaven or more like hell (81). Thus, for Lewis, life was a progression unto an eternal state: eternal joy or eternal condemnation. Of particular note is his distinction between two kinds of faith. First, is intellectual acceptance of the truth of Christianity and its teachings (115). However this faith is not merely intellectual. That is, Lewis argues that reason is not cold and divorced from the emotional life of man. Thus, when one is tempted to forego Christian beliefs about morality because it suits him, true faith is in fact a virtue, for it overcomes the emotion to retain this belief even still (116-17). Second, faith is believing something “that cannot be understood until after you have gone a certain distance along the Christian road” (119). This naturally leads the reader into the fourth and final book.
This book engages the deeper doctrine of God, including the Trinity and the Incarnation. Lewis maintains that the nature of the tri-personal God is like a cube, and it is only when we are able to perceive all of the dimensions that we are able to understand that it is made up of more than one square (133). He also attempts to tackle the idea of a timeless God, and explains that the Holy Spirit is the way in which we “catch” the spirit of God (143). Finally, he argues that it is our choice whether or not we will resist God and his actions to make us into true Sons of God (148); it is at this stage of being conformed to the image of the Son that we become our true selves (175). It is this closing thought Lewis dwells on to create a final dilemma for the reader: “Look for yourself, and you will find in the long run only hatred, loneliness, despair, rage, ruin, and decay. But look for Christ and you will find Him, and with Him everything else thrown in” (177).
Lewis accomplishes his goal of presenting a plausible version of mere Christianity for those unbelievers. He does not adjudicate between Christian denominations, nor does he intend to do so. It is important to note that there appear to be doctrines (at least one) that does not belong to the essential aspects of Christianity—namely, the defense of a timeless God. While the timelessness of God has been defended far and wide, it is now usually recognized that one is not completely outside of the pale of orthodoxy by conceiving of God as somehow in time. This is the only real bias I can detect that may impact the facts of the matter; the book was very well done!
A particular strength of Lewis is his ability to relate to the “common man,” or the outsider layman. By using both analogies and thought experiments, he is able to relate difficult concepts in a way that makes them sensible. It is true that these are not perfect analogies, but he never claims they are—and in fact takes great pains to note they are not so perfect. They do, however, tend to accomplish his goal of showing how Christian doctrine impacts life, and each individual human as well. Two particular points of emphasis will be considered.
First, Lewis considers the point of Christian virtues, given that one is saved purely of faith and not of any merit. He writes, “Now there are a good many things which would not be worth bothering about if I were going to live only seventy years, but which I had better bother about very seriously if I am going to live for ever. Perhaps my bad temper . . . might be absolute hell in a million years” (68). He exposes that the inner man is either becoming more and more like Christ, or turning inwardly into self. This is why all three facets of morality (as Lewis outlined them) matter: they are intertwined so that they affect the others!
Second, Lewis hints at here what has later been called his argument from desire. He writes, “If I find in myself a desire which no experience in this world can satisfy, the most probable explanation is that I was made for another world” (114). The critic may attempt to defeat Lewis’ underlying premise: for every natural desire there is some thing in existence that can satisfy it. Suppose someone has the desire to become the number 42, for example. There is nothing in the world that can satisfy this desire. But Lewis’ response may be two-fold. First, no one is born with such a desire. Second, if there is a natural desire present, this irrational desire is possibly reducible to it. The desire to be something else is a desire not to be inadequate, not to be limited, not to be finite, not to be contingent, not to be mortal, etc. The satisfaction of even this desire, then, may or may not be found in the world, but one can imagine that the Christian God fulfills these desires via eternal life!
Next, someone may complain that Lewis presupposes some kind of telos or purpose to human existence. It is true that if there is no purpose to human existence, then God does not exist (and neither does eternal life). However, the “common man” does not believe life to be devoid of purpose, and thus this complaint just will not do for the majority of people. Additionally, one detects a kind of proper basicality to the belief that one’s life has objective purpose.
While I found much strength to Lewis’ arguments, I did not find much about which to complain. However, two sections will be considered. First, he writes, “Almost certainly God is not in Time” (138). This is quite a contentious claim! A counterexample seems to be found in the Incarnation itself: at one point, God (Jesus) did not have human flesh (a human nature), and at another point in time he did. This, however, Lewis combats by claiming such human nature as “somehow included in His whole divine life” (139). If there are no temporal parts to the experience of God, then it seems mysterious, if not contradictory, to suggest that Jesus’ humanity was an eternal, and hence metaphysically essential, part of Jesus’ life. To see why, consider this: suppose Jesus’ human nature is a timeless part of the divine life. Further suppose God actualizes a world containing no moral agents and no human creatures. It would therefore be a puzzling thing to say that Christ should have humanity as part of his nature. So suppose a defender of Lewis makes a counterfactual claim that were it to be the case that humans were not created, then it would be the case that Jesus would lack humanity as part of the divine life. But then it would be the case that the taking on of humanity was logically posterior to the contingent decision to create free human moral agents. Thus, there is a logical part of God’s life such that he does not have Jesus taking on human nature, and Lewis’ view seems to be incorrect.
A second criticism focuses on Lewis’ “hard inclusivism.” He claims that it may be the case that God counts for righteousness the true faith of adherents of other major world religions, casting off the bad (165). This is only a minor criticism, because it does not affect his larger point in that chapter. However, it seems that he is overstating his case with respect to Old Testament saints prior to the patriarchs. It does not seem to be the case that these saints were adherents to other world religions at the same time they were regarded to be saints. At the very least, hard inclusivism seems to be more difficult to defend.
This book was an extremely powerful defense of the doctrines of mere or basic Christianity. It was aimed at the unbeliever (for a rational defense), but there is much in this work for the believer as well. First, it models for believers how to speak to unbelievers concerning the doctrines of the Gospel. Second, it helps the believers to understand aspects of the faith that they never had before. Finally, it helps believers understand that Christian truth applies to every facet of life. This book comes highly recommended for everyone, regardless of age or ability.